Portable rotary tool



Nov; 11, 1924. l 1,515,169

' A. M. POOLEY.

PORTABLE ROTARY TOOL Filed Nov. 25 1922 4 Sheets-Sheet 2 Rom?! Nov. 11 1924- 1,515,169

A. M. POOLEY PORTABLE ROTARY TOOL Filed Nov. 25 1933 4 Sheets-Sheet 5 awn 7 04 A Po 0 [8y 1 I A for My Nov. 1 1, 1924 1,515,169 l I A. M. POOLEY PORTABLE ROTARY TOOL I Filed Nov. 25 1922 4 Sheets-Sheet ,4

amt/V705 P001 ey Patented Nov. 11, 19244.

ARTHUR MILNES POOLEY, OF BEIDFOZRD, ENGLAND.

PORTABLE ROTARY TOOL.

Application filed November 25, 1922.

To all whom it may concern.

Be it known that I, ARTHUR MILNEs PooLnY, a subject of the King of England, residing at T3 Varwick Avenue, Bedford, in the county of Bedfordshire, England, have invented certain new and useful Improvements in Portable Rotary Tools, of which the following is a specification.

This invention relates to portable rotary tools such as are driven by an elastic fluid, generally compressed air. It has for its object to provide a lighter, more compact and more reliable tool of this kind.

In accordance with the invention there are combined in a structure of suitable form a turbine, a reduction gear and a tool holder with means for controlling the supply of driving fluid (hereafter spoken of as air) and suitable feed mechanism for the tool where required. The turbine will generally have a runner in the form of a single disc and is preferably of the type having approximately tangential admission of the driving fluid to a runner in the rim of which are formed, for instance. by milling, semi-circular pockets into which the stream of air enters at one side to flow in a semicircular path relative to the bucket and leave at the other side. This type of turbine is Well known for use with steam and is generally associated with the name of Stumpf. It provides for a convenient arrangement of inlet nozzles, these being arranged radially outside the wheel. Such a construction will generally run at a highspeed. for instance, 40,000 E. P. M. so that it will generally be necessary to arrange for a triple reductlon gear. Where, however,

the tool to be driven is a grinding disc or gheel, double or single reduction will suf- The invention will be further described by the aid of the accompanying drawings which illustrate by way of'example a construction which is primarily intended for use as a drill. It will be recognized however that the same or a similar construction is applicable when the machine has other functions. In the drawings, Figures 1 and 2 are sections on the lines 1, 1 of Figure 3 and 2, 2 of Figure 4 respectively. Figures 3 and 4 are views of the complete machine looked at from opposite ends. Figure 5 is a section on the line 5, 5 of Figure 4 showing an arrangement of control valve for aduitting air to the nozzles in sequence, Fig

Serial No. 603,372.

are 6 shows the nozzle plate. Figure 7 shows a section through an alternative form of nozzle control valve. Figures 8, 9 and show a form of emergency governing device adapted to cut off the air supply when the speed of the turbine exceeds what is considered to be a safe value; Figure 8 being a plan view and Figures 9 and 10 being sections on the lines 9, 9 of Figure 8 and 10, 10 of Figure 9 respectively.

The form of construction adopted is one which embodies a member 11 of plate form on one side of which is attached the turbine casing 12 while the gearing casing 13-1 1 is arranged on the other side consisting of a surrounding wall 13 and an end plate 14, the latter being approximately coextensive with the plate member 11 and combining with it to support the bearings for the spindles of the gearing and for the tool holder. Appropriate feed mechanism 15 of known kind is mounted on the plate member 11 at the same side as the turbine casing 12.

Owing to the small weight of the turbine there is no objection to mounting it 111 a position displaced considerably from the axis of the tool holder so that for the reduction, ordinary spur gearing may be employed thus avoiding the necessity for resorting to epi-cyclic gearing such as is generally considered necessary where a large reduction is to be effected between the shaft of a reciprocating motor and the tool holder The turbine disc 16 of the type previously referred to is mounted on a shaft 17 carried by a pair of ball bearings one of which is supported by an extension 18 0f the member 11 lying within the gear casing 13 (see Figure 2). End adjustment of these hearings is effected by the screw threaded cup 19 mounted in the end of the turbine casing 12 and also serving in conjunction with the cap 20 for the supply of lubricant.

The triple reduction gear comprises the following parts :A pinion 21 on the turbine shaft 17 gearing with a wheel 22 on a counter-shaft 23 which also carries the pinion 24 which gears with the wheel 25 on the second counter-shaft 26 on which is also mounted the pinion 27 driving the wheel 28 mounted on the tool holder 29.

The plate member 11 or the gear box formed thereon may have attached to it a pair of handles as usually employed for this class of tool and one of these may serve as till the air admission pipe to which the hose is attached. in the arrangements illustrated, only a single handle is shown but a second may be fitted at the other side it required. In the construction shown in Figure l the inlet passage 30 is formed in the handle which is of a type adapted for trigger control of the air supply. In the other type of construction illustrated the admission passage 30 is formed in the casting of the gear casing. The handle 31 shown in Figures 2, 4 and 5 has a continuation 32 which forms the plug part of an air admission valve and is mounted in a casing 33 arranged on the member 11 alongside the turbine casing 12.

In order satisfactorily to control the speed of the turbine for different loads, a number of separate nozzles is provided arranged to extend over an arc of the periphery of the turbine disc. These nozzles may conveniently be formed in a plate, one face of which lies approximately in the plane of one edge of the rim of the turbine runner 16, the nozzles being made by recessing this face. Such a plate 39 is shown in Figures 5 and 6 where four nozzle recesses 34, 35, 36 and 37 are shown. This plate fits on to the member 11 beneath the base 38 of the valve chamber 33 and the curved face 40 lies along the periphery of part of the runner so that the ends of the nozzles lie just clear thereof. The tur bine casing 12 is cut away to permit of the nozzle plate being fitted as indicated and to provide an exhaust opening in the adjacent part of the casing. This opening may be covered it desired by a displaceable shield (not shown in the example illustrated) adjustable into various angular positions to direct the discharge appropriately as required. Instead of forming the nozzle recesses in a separate plate these could be cut in the base 38 of the casing 33 or even in the adjacent part of the plate member 11.

In the arrangement shown in Figures 4, 5 and 6 the air coming in by the inlet 30 passes along the passage 41 and through the aperture 42 in the plate 39 and thence through the aperture 43 in the base of the valve casing. The handle 31 is rotatable through limits fixed by the engagement of the screw 44 with shoulders 45 on the end of the valve body 33. At one end position the plug member 32 closes the aperture 43 and thereby cuts of? the supply of air. As the handle is turned from this extreme position the aperture 46 n the plug 32 first makes connection with the aperture 43 thus admitting air to the hollow central part of the plug. About the same stage the aperture 47 in the plug overlaps the aperture 48 which communicates with the recess 37 in the nozzle plate thus admitting air to one nozzle. Further rotation of the handle 31 brings the apertures 49, 50 and 51 successively over the apertures 52, 53 and 54 leading to the recesses 36 35 and 34 respectively in the nozzle plate so that the number of nozzles in action is gradually increased from one to tour. In the halt way position shown in Figure 4 two nozzles 37 and 36 are receiving a full supply of air and 35 is receiving t-hrottled supply, 34 being inactive.

1n the alternative arrangement shown in Figure 7 which provides for a case where only two nozzles are employed, air passes from the chamber 55 in the handle to two nozzles by way of the passages 56 and 57 one leading to each nozzle. The valve mem. ber 58 is held in the closed position shown by a spring 59 in the chamber 55 and is moved from this position by the pressure of? the trigger 60 on the end of the spindle 61 which presses against the inside of the head of the valve member 53. To this head is attached a cylindrical body having two sets of perforations 62 and 63 which as the valve member is projected into the chamber 55 permit the passage of air from this chamber to the interior space of the valve round the spindle 61. In the first part of the movement of the valve, admission to the nozzle fed by the passage 56 only is etl ective but as the movement of the valve proceeds the end of pas sage 57 is uncovered and both nozzles come into action.

The emer 'enc '0 ernin de ic h g y b v b v e s own in Figures 3 to 10 which may in some cases be required is designed for application to a control arrangement similar to that shown in Figures 4 and 5 where a plug is retated by the handle 31. For simplicity in showing this plug and the associated parts in Figure 9, the valve plate and the pa sages leading from the interior of the valve to the nozzles have been omitted. In this arrangement, an auxiliary cut oil valve 64 is placed so as to intersect the air inlet passage 41, this valve being capable of being turned from the position shown in Figure 8 in which it is open through about 45 to close the passage when the speed o1 the turbine becomes execessive. This closing is effected by the pull of a spring 65 on an arm 66 projecting from the valve 64. Under normal conditions this movement is prevented by the engagement of a projection on the end of a catch 67 with a recess 68 in the valve 64, the engagement being maintained by the action of a spring 69. When the end of the catch 67 is removed from the recess 63 the valve 64 turns until the arm 66 comes against the stop 70. The tail of the catch 67 is held by the spring 69 in engagement with a weight 71 pivoted at 7 2 on one of the wheels of the reduction gear for instance the wheel 22 on the first countershatt, suitable structural modifications being made in the casing adjacent this wheel to accommodate the additional parts. The outward movement of the Weight 71 due to centrifugal force is resisted by the spring 78 acting upon the lever is pivoted at 75 on the Wheel and connected by a link 76 with the Weight 71. When the predetermined speed is exceeded, this centrifugal force becomes capable of moving the Weight 71 outwards and as the arrangement of the spring 73 and its connection to the Weight provides for an approximately uniform force for all posit-ions VVlLlllll the travel of the Weight, its outward movement proceeds rapidly when the predetermined speed is reached and the air supply is then cut off as previously indicated. In order to reestablish the air supply, it is necessary to return the valve 64 to its original position and this can be eli'ected by the action of turning the plug 32 to the closed position. During this turning movement the end 77 of a recess in the plug 32 comes into engagement With a projection 7 8 on the valve 64 Which projection in the closed position of that valve lies in the position shown in broken lines in Figure 10 and is moved by the engagement from that position to the position shown in full lines. This movement with the accompanying rotation of the valve 64 permits the catch 67 to reengage the recess 68 and the governor is then re-set and the main control valve 32 can then be brought into operation to restore the supply of air.

It is to be understood that While certain forms of construction have been described in considerable detail, they have been given by Way of illustration of the nature of the invention and method of carrying it into eliect rather than With the intention of indicating that the invention is limited to these details.

What I claim as my invention and desire to secure by Letters Patent is 1. A portable rotary tool structure comprising a plate member, a turbine with admission means :tor driving fluid mounted on one side of said member, a gear case mounted on the other side of said member and coniprising a side Wall and an end plate, bearings in said end plate and said member, spur reduction gearing mounted in some of said bearings and driven by the turbine, and a tool holder mounted in others of said bearings and engaging With said gearing so as to be driven thereby.

2. A portable rotary tool structure com prising a plate member, a turbine disc mounted on one side of said member With its axis at right angles thereto, nozzles for driving fluid arranged radially outside said disc and formed by recesses in a face carried by the plate member, spur reduction gearing mounted on the other side of said plate member and driven by the turbine and a tool holder driven by said gearing.

8. A portable rotary tool structure com;

prising a plate member, a turbine disc mounted on one side oi said member with its axis at right angles thereto, nozzles for driving fluid arranged radially outside said disc and formed by recesses in a face carried by the plate member, a combined valve and handle member controlling the admission of fluid to said nozzles and serving for the support and guidance of the structure, spur reduction gearing mounted on the other side of said plate member and driven by the turbine and a tool holder driven by said gearing.

4. A portable rotary tool structure comprising a plate member, a turbine disc mounted on one side of said member with its axis at right angles thereto, nozzles for driving fluid arranged radially outside said disc and formed by recesses in a face carried by the plate member, a combined valve and handle member controlling the admission of fluid to said nozzles in sequence and serving for the support and guidance of the structure, spur reduction gearing mounted on the other side of said plate member and driven by the turbine and a tool holder driven by said gearing.

5. A portable rotary tool comprising in combination a turbine disc, a reduction gear driven by said turbine, a tool holder driven by said gear, a set of nozzles radially out side and immediately adjacent to the turbine disc, said nozzles being formed by recesses in a face lying approximately in the plane of one edge of the turbine disc.

6. A portable rotary tool comprising in combination a turbine disc, a reduction gear driven by said turbine, a tool holder driven by said gear, a set of nozzles radially outside and immediately adjacent to the turbine disc, said nozzles being formed by recesses in a face lying approximately in the plane of one edge of the turbine disc, hand controlled means for admitting driving fluid to said recesses in sequence for the purpose of controlling the speed and power of the tool.

7. A portable rotary tool structure comprising in combination a turbine, a reduction gear driven by the turbine, a tool holder driven by the reduction gear, nozzles for the admission of fluid to the turbine, a

valve chamber having a series of ports one for each of said nozzles, a rotatable plug valve fitting in said chamber, a handle connected With said valve and serving for actuating it and for supporting the structure, means for leading fluid into said chamber and ports in said plug valve for admitting fluid from said chamber to the nozzles in sequence as the valve is rotated.

8. A portable rotary tool structure comprising a plate member, a turbine mounted on one side of said member With its axis at right angles. the eto, nozz e f r d i ing 41, 1,515 ice fluid arran 'ed radially outside said disc and -formed by recesses in a far: carried by said member, a v e casing mounted on said member over the nozzle recesses and h 2' in; ports communicating wit said rec rotatable valve member in said casing. supporting and valve ring handle projecting 'lroin casing, reduction driven by said turbine and a tool holder driven by said reduction gear.

9. A portable rotary tool comprising tool holder, transmission means through which said holder is driven, a turbine actuating said transmission means, a set of nozzles supplying driving fluid to said turbine, valve means for admitting driving fluid to said nozzles in sequence so as to obtain a graduated supply of power and a handle member controlling said valve means and serving as a support for the tool.

10. A portable rotary tool structure comprising a flat boil frame, a tool holder car ried by said frame, reduction gearing mounted within said frame and engaging said tool holder, a turbine disc mounted on the outside of said frame, a transmission member actuated by said turbine disc and passing within said frame and engaging with the reduction gear so as to impart motion thereto, a nozzle plate carried on the outside o'l said frame directly adjacent to and surrounding a portion of the periphery of said disc, the said plate having formed in it a series of recesses shaped so as to serve as nozzles, a valve casing mounted on said frame over said plate closing one side of the nozzle recesses, ports in said casing communicating with the recesses and valve means in said casing for admitting driving fluid to said ports in sequence.

11. A portable rotary tool structure comprising in combination a turbine, a reduction gear driven by the turbine, a tool holder driven by the reduction gear, nozzles tor the admission of fluid to the turbine, hand controlled means for bringing said nozzles into and out of action, a second means for putting said nozzles out of action and a speed governor controlling said second means so as to cut ed the supply 01 driving :lluid when the speed of the turbine becomes excessive.

l2, A. portable rotary tool structure comprising in combination a turbine, a reduc tion gear driven by the turbine, a tool holder driven by the reduction gear, nozzles tor the admission rt. fluid to the turbine, a hand control valve for said nozzles, a second valve for said nozzles, means for retaining said second valve in the open position, a speed governor driven by the turbine and means for releasing said valve holding means and closing said valve under the control of the governor.

13. A portable rotary tool structure conr prising in combination a turbine, a reduo' tion gear driven by the turbine, a tool holder driven by the reduction gear, nozzles for the admission of fluid to the turbine, 21 hand control valve tor said nozzles, a second valve for said nozzles, means for retaining said second valve in the open position, a speed governor driven by the turbine and means for releasing said valve holding means and closing said valve under the control of the governor, means for interconnecting the two valves so that after the closing of the governor controlled valve it is reset in the open position by the movement of the hand controlled valve to the closed position.

14:. A portable rotary tool structure comprising in combination a turbine, a reduction gear driven by the turbine, a tool holder driven by the reduction gear, nozzles for the admission of fluid to the turbine, a hand controlled rotary plug valve for said nozzles and a governor controlled rotary plug valve also controlling the supply of fluid to said nozzles, said second plug valve having a projection engaging in a recess in the first plug valve so that When the second valve is in the closed position the projection lies in the path of one end of the recess in the other valve and thereby the second valve is moved to the open position when the lirst valve is brought to the closed position.

ln testimony whereof I aliix my signature.

ARTHUR MILNES POOLEY. 

